1. Field of the Invention
This invention relates to a specific class of alkoxylated novolak resin compositions useful in defoaming and inhibiting foam formation in systems of many types, and preferably in normally aqueous systems.
2. Description of the Prior Art
Alkoxylated novolak resin compounds of various structures are well known. Materials of this type are useful as surface agents, as defoamers, as emulsion breakers, particularly petroleum emulsion breakers, etc. Particular reference may be made to U.S. Pat. Nos. 2,076,624; 2,499,360-370; 2,914,484; 3,202,615; 3,684,735; 3,048,548; 3,082,172; and 3,382,178.
However, in order to synthesize an alkoxylated novolak for a particular end-use, such as a foam inhibitor or defoamer, it is necessary that the chemical structure be carefully tailored in a chemical sense so that the derived activity is obtained. It is important that both the basic structure of the molecule such as initiator, and alkylene oxide or mixture of alkylene oxide reagents be carefully chosen to achieve a final molecule of requisite activity. Thus, for example, depending upon its structure, and/or process of making, a particular alkoxylated novolak may act in one case as a foam generator and in another situation as a foam suppressant.
It therefore becomes an object of the invention to provide a new class of compositions useful in inhibiting foam formation and/or collapsing already foamed systems. A more specific object of the invention is to provide a defoamer composition useful in inhibiting defoaming foam formation in aqueous systems, and particularly in dishwater containing detergents used for washing. Other objects will appear hereinafter.